Process for producing organolead compounds



United States Patent This invention is a division of my "co-pending application Ser. No. 507,993, filed May 12, 1955 and relates to a process of producing organic compounds of the elements of the groups H to V of the periodic table and is more particularly concerned with a process of introducing organic radicals into fluorides of certain elements by means of an organic aluminum compound.

The introduction of organic radicals into inorganic metallic compounds has been attempted in various ways and several processes have been proposed. These processes, however, have suffered from one or more drawbacks, such as diflicultly-obtainable reagents, poor yields, handling problems, and the like, which have limited their industrial utility.

It is the object of the present invention to provide a process for introducing organic radicals, particularly hydrocarbon radicals, into inorganic metallic compounds which avoids the drawbacks and disadvantages of processes heretofore proposed.

In accordance with the invention, compounds of the formula MR, are formed wherein M is an element of groups II to V, inclusive, of the periodic table, R is a hydrocarbon radical, and x is an integer corresponding to the valence of the element M, by reacting a fluoride or complex fluoride of the element M with an organic aluminum compound containing the radical R. In accordance with the invention, M is preferably an element of groups IIB, IIIA, IVA or VA of the periodic table as set forth, for example at page 312 of the thirtieth edition of the Handbook of Chemistry and Physics. Partioularly suitable are fluorides and complex fluorides (particularly complex fluorides containing an alkali metal in the molecule) of antimony, arsenic, boron, cadmium, lead, mercury, phosphorus, tin and zinc. Examples of such fluorides and complex fluorides of M employable in accordance with the invention are, BF AsF SbF SnF,, ZIlFg, PbF CdF KBF, and KAsF The organic aluminum compounds which are reacted with the fluorides and complex fluorides of the element M are aluminum compounds containing the radical R wherein R is an alkyl radical, an aryl radical, or an .aralkyl radical or ether coordination compounds of such aluminum compounds, e.g. diethyl ether and dimethyl ether coordination compounds. When R is an alkyl radical it preferably contains 1 to 12 carbon atoms, such as methyl, ethyl, propyl, butyl and the like. When R is an aryl radical, it preferably contains 6 to 12 carbon atoms, such as phenyl, tolyl, xylyl and the like, and when R is an aralkyl radical it is preferably a benzyl radical or a benzhydryl radical or hydrocarbon-substituted derivative thereof.

3,072,697 Patented Jan. 8,- 1963 action temperature employed is between 10 and 250 C., preferably 80 to, 180 C., and the reaction may be carried out at atmospheric pressure or under superatmospheric pressure, in any suitable pressure vessel. The reaction may be carried out in the absence of solvents or in the presence of inert solvents such as benzene, toluene, hexane, and like inert hydrocarbons.

The reaction takes place, for example, according to the following equations:

The following specific examples are further illustrative of the inventionfall parts being by weight:

Example 1 228 parts of aluminum triethyl are heated to about 90 to 130 C. and gradually mixed, while stirring, with a total of 103 parts of ZnF Zinc diethyl is formed according to the formula and distills off at 112 C. with a yield of over 75%. Subsequently the aluminum diethyl fluoride which is formed as a by-product of the above reaction is distilled off in vacuo. It is a colorless liquid which has only a slight tendency to flow at room temperature.

Example 2 114 parts of aluminum triethyl are dissolved in 300 parts of anhydrous hexane and brought to reaction by adding in drops, while stirring, 132 parts of arsenic trifluoride. The reaction is very vigorous even at room temperature (about 20 C.). The arsenic triethyl which is formed is distilled off at about 140 to 142 C. after the hexane has been removed by distillation. The yield of arsenic triethyl is more than 80% of the theoretical.

Example 3.

114 parts of aluminum triethyl are gradually mixed at room temperature with a total of 75 parts of cadmium fluoride. Cadmium diethyl is formed according to the formula The cadmium diethyl thus formed (B.P. 10 mm. 42-

45 C.) as well as the diethyl aluminum fluoride which i is formed as by-product are separated by distillation. The

The reaction between the organic aluminum compound yield of cadmium diethyl is more than Example 4 188 parts of aluminum-diethyl diethyl-etherate are added in drops to 186 parts of potassium fluoborate, which has been previously heated in an oil bath to 180 C. The reaction, which starts immediately, is at first very vigorous but then becomes gradually slower as the addition of the aluminum-diethyl diethyl-etherate progresses. The boron triethyl which is formed is separated from the reaction mixture by distillation and is recovered in a yield of Example 5 206 parts of aluminum-triethyl diethyl-ethera-te, diluted with equal parts of ether, are added in drops, while stirring and cooling, to 132 parts of arsenic fluoride. The reaction is instantaneous. After separation of the ether, of the theoretical yield of arsenic triethyl (B.P. 138141 C.) is recovered from the reaction vessel.

Example 6 21.5 parts of antimony t'rifluoride are suspended in 55 parts of ether, and 18.8 parts of aluminum-triethyl diethyl-etherate are added in drops while stirring. The reaction proceeds smoothly and antimony triethyl is formed. This product (8.1. 56' C./10 mm.) is distilled off by vacuum distillation after the ether has been removed by simple distillation. The yield is 60% of the theoretical.

Example 7 114 parts by weight of ARC- H are added in drops while stirring to 129 parts by weight of KBF. which is heated in a glass flask to 160-170 C. Boron triethyl forms immediately and is distilled ofi as the aluminum triethyl is added. After the total amount of aluminum triethyl had been added, about 60% of the theoretical yield of boron triethyl is formed. Finally, the mixture remaining in the reaction flask is heated to 220-250 C. and after the reaction has finished, a total of 89 parts of boron-triethyl are obtained, which corresponds to a yield of 91% of the theoretical.

Example 8 179 parts of freshly sublimated antimony trifluoride are added gradually, with stirring, at 120-135 C. during the course of 116 hours to 342 parts of aluminum triethyl contained in a three-necked flask under nitrogen. The reaction starts immediately after each addition of antimony trifluoride. After the total quantity of antimony trifluoride has been added, the mixture is heated briefly to 140' C. to complete the reaction. The antimony triethyl, formed is distilled ofi in vacuo in 90% yield relating to the formula Example 9 Lead tetraethyl can be obtained from lead fluoride and aluminum-triethyl in a manner similar to that de- 4 scribed in Example 5. The lead diethyl formed in the first stage of the reaction decomposes immediately, forming lead tetraethyl and lead according to the formula or can be extracted from it by known solvents for this.

compound.

Example 10 A pressure vessel is charged with equimolar amounts of aluminum triethyl and boron fluoride. The reaction starts immediately, with the temperature rising up to about C. To complete the reaction heating is continued briefly at about 200' C. The yields are almost quantitative, both with regard to aluminum triethyl and boron fluoride. Boron triethyl can also be produced by simply introducing boron fluoride into aluminum triethyl, but the yields of boron triethyl are much higher when working under pressure, e.g. a pressure of 5 to 50 atmospheres.

Instead of AIR, it is possible to use as in the most examples previously stated AlR F (e.g. issued as by-product according to the Examples 1, 3 and 8) as means for alkylation. The end product of the process of this aluminum-organic compound is then AlF, with very small quantities of impurities with AlRF,.

I claim:

1. A process of producing a hydrocarbon lead compoundwhich comprises reacting a lead fluoride with a hydrocarbon aluminum compound wherein the hydrocarbon portion of said compound is selected from the group consisting of alkyl and aryl radicals.

2. The process as claimed in claim 1 wherein said bydrocarbon aluminum compound is triethyl aluminum.

References Cited in the file of this patent UNITED STATES PATENTS Blitzer et a1. May 23, 1961 3 072 697 January 8 1963 Patent N00 Herbert Jenkner above numbered pathao error appe tent should read as eroified t that the said Letters Pa It is hereby o cation and ent requiring corre corrected below.

tothe and in the heading each In,the grant lines 2 and 11,

"Kali-*Chemi AaGg printed specification line 5 for Kali-=Chemie A.G "0

occurrence, read Signed and sealed this 9th day of July 1963a SEAL) Attestz' DAVID L. LADD 'ERNEST w. SWIDER Commissioner of Patents Attesting Officer 

1. A PROCESS OF PRODUCING A HYDROCARBON LEAD COMPOUND WHICH COMPRISES REACTING A LEAD FLUORIDE WITH A NYDROCARBON ALUMINUM COMPOUND WHEREIN THE HYDROCARBON PORTION OF SAID COMPOUND IS SELECTED FROM THE GROUP CONSISTING OF ALKYL AND ARYL RADICALS. 